TPI mods, then MISFIRE that won't quit

[rel3rd]

Here's what it sounds like...does it now even sitting still just revving it up:

http://www.youtube.com/watch?v=hD4R08CVQDw

 

[KANE]

A quick history....
Car is 85 Corvette, L98 TPI .....

When it misfires, it backfires and/or pops through intake and exhaust at the same time. I can best describe it as the sound of a blower car getting spark blown out, or a wiped cam. If I ease into throttle, up to 5800 rpm's, it doesn't misfire. If I rapidly open throttle, it misfires at least half the time, maybe more since it seems to be getting worse.

Charging system is fine. (14.2 volts at idle)
Fuel pressure doesn't fluctuate at all at WOT (38psi)
Timing at stock 6*
Misfires only at WOT (or at least that's when I can feel/hear it.

Any help greatly appreciated

Check engine light- do you get codes if you jump the ALDL?

Since you say you have an 85- I assume it is still MAF. How about your knock sensor- I wonder if you are outside the upper control limit for that sensor...

Look on this site-Craig might be able to help with
http://www.moates.net/

or-
http://www.diy-efi.org/gmecm/ecm_info/

 

[rel3rd]

Check engine light- do you get codes if you jump the ALDL?

Since you say you have an 85- I assume it is still MAF. How about your knock sensor- I wonder if you are outside the upper control limit for that sensor...

Look on this site-Craig might be able to help with
http://www.moates.net/

or-
http://www.diy-efi.org/gmecm/ecm_info/

No codes whatsoever.
Yes, still MAF.
I wanted to unplug the knock sensor, but haven't yet done it.
I actually downloaded the WinALDL program and was monitoring the sensors today, but when I tried to datalog them, the laptop turned itself off and I haven't been able to get the program working again. ad

 

[casper]

HI Guys

Pse provide website for this datamaster stuff. Where can I source a connection cable / diagram

Thanx

casper

 

[rel3rd]

Thanks for the replies guys.

Cam is wiped....#7 exhaust rocker has maybe half the movement of all the others.